all right, i've reseted one more time the sun and with final quality renderworks, indirect lighting to normal (2) and hdri white it's working!!! it is a bit burned but I suppose that some settings could change that..... for those who have same problem I suggest them to clean there lights and put new ones.
what do you think about this render? what should I do to make it better?
thank you for helping me, I hope this will help others too.